Update documentation about widechar
Update documentation about widechar

widechar definition was changed from a #define to a typedef
(see commit 509cee05ff)
BueVest/liblouis,BueVest/liblouis,liblouis/liblouis,liblouis/liblouis,BueVest/liblouis,hammera/liblouis,hammera/liblouis,BueVest/liblouis,hammera/liblouis,hammera/liblouis,liblouis/liblouis,hammera/liblouis,liblouis/liblouis,BueVest/liblouis,BueVest/liblouis,hammera/liblouis,liblouis/liblouis,liblouis/liblouis